.header{
    width: 100%;
    height: 500px;
}
.left{
    width: 15%;
    height: 500px;
    background-color: #ffffc4;
    float: left;
    border: 2px solid darkcyan;
    border-radius: 10px;
}

.medium{
    width: 60%;
    height: 500px;
    background-color: sandybrown;
    float: left;
    border-radius: 15px;
}

.right{
    width: 24%;
    height: 500px;
    background-color: skyblue;
    float: left;
    border-radius: 10px;
}

.d1{
    width: 600px;
    height: 300px;
    background-color: skyblue;
    font-size: 50px;
    padding-top: 50px;
    padding-left: 100px;
    margin-top: 200px;
}